1. Field of the Invention
This application relates to the field of firearms particularly telescoping buttstock mechanisms. More specifically it concerns an improvement to the M4 style and its derivative telescoping buttstocks found on many modern adjustable-for-length firearms.
2. Description of Prior Art
The telescoping buttstock has been fielded by many nations since the advent of modern mechanized warfare moved soldiers into vehicles. Telescoping is defined as an axial longitudinal movement collinear with the barrel and action assembly of the firearm. Early submachine guns utilized a wire type telescoping buttstock in order to decrease the overall length of the weapon when it was not in use. The advantage to such a mechanism is the speed with which the arm can be readied from its collapsed position. Many styles of telescoping buttstock have been created since their introduction but none have been as ubiquitous as the M4 style that was originally created for the M16 family of rifles. Roy in U.S. Pat. No. 3,348,328 took the basic use of a telescoping buttstock and added the extra feature of a number of stopping positions located vertically in the buffer tube or receiver extension. Each position may be locked into by depressing the lever to disengage the locking pin in one position and sliding the stock lengthwise to another position and releasing the lever. This then allows the locking pin to engage vertically in the desired locking detent position. This shall henceforth be referred to as the M4 type adjustable buttstock.
Thus the trigger pull length could be tailored to each shooter that is issued a rifle. This new family of telescoping (or adjustable) buttstocks is today available for and used on rifles, submachine guns, shotguns (as shown by Kay in U.S. Pat. No. 6,662,485) and even belt fed machineguns. It has become the de facto standard due to its end user adaptability. It has a flaw in use, however, in that with the exception of the furthest position a user is unable to immediately ready their weapon from the completely collapsed position. This is due to the fact that there are a number of possibly positions and the user must pass over the undesired detents in order to find that which they prefer. This can be time consuming and in a combat situation, life threatening.
Fitzpatrick et al in U.S. Pat. No. 7,762,018 B1 creates a new assembly of parts to accomplish the length of pull adjustments but also includes the ability to preset the buttstock to a desired position. This however requires an entirely new buttstock to be installed on the gun after previously removing the older, more commonplace and standardized version.